Steven Schaffer

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This paper describes Gamebots, a multi-agent system infrastructure derived from an Internet-based multi-player video game called Unreal Tournament. The game allows characters to be controlled over client-server network connections by feeding sensory information to client players (humans and agents). Unlike other standard test-beds, the Gamebots domain(More)
OBJECTIVES Determine the effect of early (days 3-5) or late (days 10-14) tracheostomy on intensive care unit length of stay (ICU LOS), frequency of pneumonia, and mortality, and evidence of short-term or long-term pharyngeal, laryngeal, or tracheal injury in head trauma, non-head trauma, and critically ill nontrauma patients. STUDY DESIGN Randomized,(More)
beta-Carotene and Retinol Efficacy Trial is a nationwide chemoprevention trial that recruited 18,314 high-risk individuals to test the effect of supplemental beta-carotene and retinol on lung cancer incidence. In this report, we conducted a prospective nested case-control study of the association between serum carotenoids, retinoids, and tocopherols on both(More)
Epidemiological studies have suggested that low levels of selenium are associated with a higher incidence of both lung and prostate cancer. We analyzed the selenium serum concentration in 356 Carotene and Retinol Efficacy Trial (CARET) participants who later developed lung cancer and 356 matched controls and in 235 prostate cancer cases and 456 matched(More)
The term pneumocele refers to an expansile bone destructive air containing cyst-like lesion involving the sinus cavity proper, presumably due to obstruction of the major sinus ostium. It differs from pneumoceles described previously that have all been air pockets beyond a paranasal air sinus due to an abnormal fistulous communication, rather than expansion(More)
Since its approval by the Food and Drug Administration in September 1985, the Garren-Edwards gastric bubble has been extensively used as an adjunct to diet and behavioral modification in the treatment of exogenous obesity. In an attempt to evaluate the efficacy of the Garren-Edwards gastric bubble, a double-blind crossover study was undertaken. Ninety(More)
To determine the incidence and clinical significance of otitis media in traumatized adults requiring intubation, 67 adult trauma patients admitted to a level-I trauma center over a 6-month period who required three or more days of intubation were examined otoscopically for the presence of otitis media. Eleven of these intubated brain-injured patients had(More)
3541 Background: BV, a monoclonal antibody against vascular endothelial growth factor, provides a survival advantage when added to first line therapy for metastatic colorectal cancer. CAP allows for fluoropyrimide treatment without the inconvenience of an infusion pump. We aimed to investigate the combination of OX, CAP, and BV (XeloxA) as a more convenient(More)
Imaging spectrometers are valuable instruments for space exploration, but their large data volumes limit the number of scenes that can be downlinked. Missions could improve science yield by acquiring surplus images and analyzing them onboard the spacecraft. This onboard analysis could generate surficial maps, summarizing scenes in a bandwidth-efficient(More)